Farms are places of year-round activity. There is almost always something going on, regardless of the season. Each month we highlight one of our research stations and the work taking place on the farm during that month as well as give a little insight into the world of farming and innovative agricultural research.
There are 18 research stations across the state, operated in partnership between the department, N.C. State University and N.C. A&T State University. The stations are strategically located to account for different soil types, climates, crops and livestock production. Department staff manage the day-to-day operations of the stations and the research field work, while researchers from the universities set up the parameters of the research. This month we are highlighting the Horticultural Crops Research Station in Clinton.
North Carolina is the No. 1 producer of sweet potatoes in the United States, so it’s safe to assume there is a fair amount of research being conducted in the state on these nutritional powerhouses. The Horticultural Crops Research Station serves as a kind of home base for all the sweet potato research being conducted in the state, housing specialized equipment and storage, said Ken Pecota, an NCSU sweet potato researcher.
Research is focused on developing new varieties of table-stock potatoes, new varieties that are better suited for sweet potato fries and chips, work on purple-fleshed potatoes for pigment extraction and research on ornamental varieties, Pecota said. With the growth in popularity of sweet potato fries and chips comes growth in demand for sweet potatoes and sweet potato products.
Rodney Mozingo, the research operations manager at the Clinton station, said this is an especially busy time of the year at the station, although recent rains have delayed efforts to get in the field. The station is raising plants in plant beds and greenhouses, where they are waiting to be transplanted to the fields. Most of the day-to-day work right now is focused on getting the land prepped for planting, which should happen in the next week or two, Mozingo said.
The recent rains presented more challenges to what has been a cool, wet spring. Workers have had to wait for the soil to dry out some to prep the fields. Even though tractors can run through the wet fields, going into them with heavy machinery before they dry out enough would end up creating a rutted mess that could cause problems all season long.
“You have to take advantage weather-wise whenever you can get in the field,” Mozingo said. “Agricultural research doesn’t have eight- or nine-hour work days. When the field conditions are right and the timing is right for planting, it means coming in early and staying late. There is a short window of time and you’ve got to get it done when you can.”
Unlike Irish potatoes, which grow from a seed potato, sweet potato plants sprout from roots that have been laid out on the ground and covered with one to two inches of soil in a process known as bedding. When these plants are 10 to 12 inches tall, known as slips, they are cut and transplanted to the field. “It is amazing how hardy the sweet potato plant is,” Mozingo said.

Sweet potato plants in the greenhouse at the Horticultural Crops Research Station in Clinton await transplanting to the fields.
Farmers in the state are primarily growing the Covington variety, which was released in 2005, but Pecota said researchers are looking for another variety to eventually replace the Covington.
There are many qualities researchers look for in testing new varieties. The breeding program evaluates promising new lines for 43 different traits needed for a successful new variety. Taste, storage and processing capabilities, disease resistance, good size distribution, good shape, skin and flesh color and plant architecture are among the many characteristics being evaluated. Pecota said it takes seven years to evaluate new varieties.
Consumer interest in sweet potato fries are behind research into varieties suitable for fries. If several major quick-serve chain restaurants began carrying the sweet potato fries, acreage would have to increase significantly to meet demand. Pecota said chains are looking for alternatives because of weaker demand for traditional potatoes.
“It’s a good time to be in sweet potato research after a 50-year slide. We’ve finally caught the upswing,” Pecota said.
Sweet potatoes are not the only labor-intensive crops at the Horticultural Crops Research Station. The station also produces tomatoes, cucumbers and watermelons. All these crops have to be harvested by hand. The station has 13 full-time employees, and adds up to seven more temporary workers during harvest time.